In WordPress 3.4 you have something called Theme Customizer that provide a optionpanel within wp-admin that enables you to see the changes in real-time. Maybe thats an option to go?
Look at this video to see how it works: http://www.youtube.com/embed/amUjCfpIsJ4
Then you have themes like Headway that you can change the theme appearance on the front-end and add your own settings.